U.S. patent application number 10/267061 was filed with the patent office on 2003-07-24 for polyester coetherified melamine formaldehyde copolymers.
This patent application is currently assigned to OMNOVA Solutions Inc.. Invention is credited to Fay, Martin, Garcia, Guillermina C., Robbins, James E., Weinert, Raymond J..
Application Number | 20030138650 10/267061 |
Document ID | / |
Family ID | 27807220 |
Filed Date | 2003-07-24 |
United States Patent
Application |
20030138650 |
Kind Code |
A1 |
Fay, Martin ; et
al. |
July 24, 2003 |
Polyester coetherified melamine formaldehyde copolymers
Abstract
In a first embodiment a polyoxetane-polyester polymer comprising
a hydroxyl terminated polyoxetane prepolymer containing repeat
units derived from polymerized oxetane monomers having one or two
pendant --CH.sub.2--O-- (CH.sub.2).sub.n-Rf groups wherein Rf is
partially or fully fluorinated, where the polyoxetane prepolymer is
esterified with polyester forming reactants to form the
polyoxetane-polyester polymer, and said polymer is mixed with a
reactive lower alkyl etherified melamine formaldehyde to form a
thermoformable coating composition. In a second embodiment, the
coating composition is based on a polyester mixed with the lower
alkyl etherified melamine formaldehyde and is substantially free of
the polyoxetane. The coating composition is partially cured in a
first stage heating at less than about 180.degree. F. to provide a
thermoformable partially cured, tack-free, non-blocking, coating
layer, followed by application to generally a contoured substrate
and thermoformed to conform thereto. The contoured partially cured
coating layer is then heat cured at temperatures above at least
180.degree. F. for time sufficient to form a cured coating.
Inventors: |
Fay, Martin; (Orwrigsburg,
PA) ; Garcia, Guillermina C.; (Copley, OH) ;
Weinert, Raymond J.; (Macedonia, OH) ; Robbins, James
E.; (Twinsburg, OH) |
Correspondence
Address: |
HUDAK, SHUNK & FARINE, CO., L.P.A.
2020 FRONT STREET
SUITE 307
CUYAHOGA FALLS
OH
44221
US
|
Assignee: |
OMNOVA Solutions Inc.
|
Family ID: |
27807220 |
Appl. No.: |
10/267061 |
Filed: |
October 8, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10267061 |
Oct 8, 2002 |
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10091754 |
Mar 6, 2002 |
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10091754 |
Mar 6, 2002 |
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09698554 |
Oct 27, 2000 |
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09698554 |
Oct 27, 2000 |
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09384464 |
Aug 27, 1999 |
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6383651 |
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09384464 |
Aug 27, 1999 |
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09244711 |
Feb 4, 1999 |
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6423418 |
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09244711 |
Feb 4, 1999 |
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09035595 |
Mar 5, 1998 |
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Current U.S.
Class: |
428/482 ;
428/480; 525/437; 525/441 |
Current CPC
Class: |
C08G 63/6824 20130101;
Y10T 428/31786 20150401; C08J 2467/00 20130101; C09D 167/00
20130101; C08J 3/244 20130101; Y10T 428/31794 20150401; C08G 63/682
20130101; C08G 18/10 20130101; C08L 67/00 20130101; C08J 7/0427
20200101; C08G 65/226 20130101; C08G 65/18 20130101; C08J 2367/00
20130101; C08L 61/20 20130101; C08G 18/5015 20130101; C08J 7/046
20200101; C09D 167/00 20130101; C08L 2666/16 20130101; C08G 18/10
20130101; C08G 18/46 20130101; C08L 67/00 20130101; C08L 61/20
20130101; C09D 167/00 20130101; C08L 2666/14 20130101; C09D 167/00
20130101; C08L 61/20 20130101 |
Class at
Publication: |
428/482 ;
428/480; 525/437; 525/441 |
International
Class: |
C08F 020/00 |
Claims
What is claimed:
1. A process for forming a laminate, comprising the steps of:
applying a mixture of a coating composition comprising a blend of a
polyester polymer and an alkyl etherified melamine formaldehyde to
a substrate and forming a laminate; partially curing said coating
of said laminate, and subsequently thermoforming and crosslinking
said coating composition.
2. The process for forming a laminate according to claim 1, wherein
said coating is partially cured at a temperature of about
49.degree. C. to about 82.degree. C., wherein said crosslinking
occurs at a temperature of at least about 83.degree. C., wherein
said alkyl etherified melamine formaldehyde comprises melamine
formaldehyde etherified with at least one alkyl group, and wherein
each said alkyl group, independently, contains from 1 to 6 carbon
atoms.
3. The process for forming a laminate according to claim 2, wherein
said alkyl etherified melamine formaldehyde has at least two
different alkyl groups.
4. The process for forming a laminate according to claim 3, wherein
said alkyl groups have a carbon atom differential of at least two
carbon atoms.
5. The process for forming a laminate according to claim 4, wherein
said alkyl groups comprise methyl and butyl.
6. The process for forming a laminate according to claim 1, wherein
said partially cured coating composition has an elongation
extensibility of at least about 150% at 82.degree. C.
7. The process for forming a laminate according to claim 4, wherein
said partially cured coating composition is crosslinked at a
temperature of from about 88.degree. C. to about 149.degree. C.
8. The process for forming a laminate according to claim 1, wherein
said polyester polymer is derived from a polycarboxylic acid having
from 3 to about 30 carbon atoms and from a polyhydric alcohol
having from 2 to about 20 carbon atoms.
9. The process for forming a laminate according to claim 8, wherein
said polyester polymer is derived from adipic acid, isophthalic
acid or phthalic anhydride or a combination thereof, from
2,2-dimethyl-1,3-propan- ediol, trimethylol propane, and
cyclohexane dimethanol, and wherein said amount of said alkyl
etherified melamine formaldehyde crosslinking resin is from about
10% to about 70% by weight based upon the total weight of said
polyester and said alkyl etherified melamine formaldehyde
composition.
10. The process for forming a laminate according to claim 9,
wherein said alkyl groups comprise methyl and butyl.
11. The process for forming a laminate according to claim 1,
wherein said coating is substantially free of a fluorinated
polyoxetane.
12. The process for forming a laminate according to claim 4,
wherein said coating contains less than about 2% by weight of a
fluorinated polyoxetane, and wherein said polyester polymer is
derived from a polycarboxylic acid having from 3 to about 30 carbon
atoms and from a polyhydric alcohol having from 2 to about 20
carbon atoms.
13. The process for forming a laminate according to claim 1,
wherein said substrate is a thermoformable polymer.
14. The process for forming a laminate according to claim 4,
wherein said substrate is polyvinyl chloride.
15. The process for forming a laminate according to claim 8,
wherein said substrate is a thermoformable polymer for an article
of furniture.
16. An article of furniture, comprising: a thermoformed laminate
comprising a coating on a substrate adhered to the article, said
coating comprising a polyester polymer reacted with an alkyl
etherified melamine formaldehyde which is cured on said substrate
in at least two stages.
17. The article of claim 1 6, wherein said etherified melamine
formaldehyde comprises melamine formaldehyde etherified with at
least two alkyl groups, wherein each said alkyl substituent group,
independently, contains from 1 to 6 carbon atoms, and wherein said
coating is partially cured at a first temperature, and subsequently
crosslinked at a higher temperature.
18. The article of claim 17, wherein said alkyl groups have a
carbon atom differential of at least two carbon atoms.
19. The article of claim 18, wherein said coating is partially
cured at a temperature of from about 49.degree. C. to about
77.degree. C. and subsequently crosslinked at a temperature of
about 82.degree. C. to about 149.degree. C.
20. The article of claim 19, wherein said polyester polymer is
derived from a polycarboxylic acid having from 3 to about 30 carbon
atoms and from a polyhydric alcohol having from 2 to about 20
carbon atoms.
21. The article of claim 20, wherein said polyester is derived from
adipic acid, isophthalic acid or phthalic anhydride, or combination
thereof, from 2,2-dimethyl-1,3-propanediol, trimethylol propane,
and cyclohexane dimethanol, and wherein said amount of said alkyl
etherified melamineformaldehyde crosslinking resin is from about
10% to about 70% by weight based upon the total weight of said
coating composition and said etherified melamine formaldehyde
resin, and wherein said alkyl groups of said melamine formaldehyde
comprise methyl and butyl.
Description
CROSS REFERENCE
[0001] This is a continuation-in-part of prior application Ser. No.
10/091,754, filed Mar. 6, 2002 entitled TWO STAGE THERMOFORMABLE
FLUORINATED POLYOXETANE-POLYESTER COPOLYMERS, which is in turn a
continuation-in-part of prior application Ser. No. 09/698,554,
filed Oct. 27, 2000 entitled CURED POLYESTER CONTAINING FLUORINATED
SIDE CHAINS, which in turn is a continuation-in-part of prior
application Ser. No. 09/384,464, filed Aug. 27, 1999, entitled
POLYESTER WITH PARTIALLY FLUORINATED SIDE CHAINS, which in turn is
a continuation-in-part of prior application Ser. No. 09/244,711,
filed Feb. 4, 1999, entitled EASILY CLEANABLE POLYMER LAMINATES,
which in turn is a continuation in part of prior application Ser.
No. 09/035,595, filed Mar. 05, 1998, entitled EASILY CLEANABLE
POLYMER LAMINATES, all five of which are herein incorporated by
reference.
FIELD OF INVENTION
[0002] This invention pertains to thermoformable coatings applied
to substrates, and more particularly to typically two stage heat
curable coatings applied to thermoformable substrates such as
plastics. The coating is partially cured in a first stage to form a
thermoformable coating layer adhered to the substrate, and heat
cured in a second stage to additionally cure the coating and
provide a hard surface coating on an article having a desired
configuration.
[0003] More specifically, in a first embodiment this invention
relates to fluorinated polyoxetane-polyester polymers containing
polyoxetane derived from polymerizing oxetane monomers having
partially or fully fluorinated pendant side chains.
Polyoxetane-polyester polymers have many of the desirable
properties of fluorinated polymers and the ease of processability
of polyesters. The desirable properties of the fluorinated oxetane
polymers are due to the fluorinated side chains and the tendency of
the fluorinated side chains to be disproportionately present at the
air exposed surface when cured. The fluorinated
polyoxetane-polyester polymers are cured with an alkyl modified
melamine formaldehyde crosslinker comprising an alkyl etherified
melamine formaldehyde resin.
[0004] In a second embodiment, it has been discovered that a
suitable coating for various applications can be made with a
polyoxetane free polyester and cured in a multi stage process.
Specifically, the coating comprises a polyester which is cured
using an alkyl modified melamine formaldehyde cross-linking agent,
more specifically, alkyl etherified melamine formaldehyde.
Evaluation of these polyoxetane free compositions indicate that
they have a good balance of properties and are suitable for coating
thermoformable substrates.
BACKGROUND OF INVENTION
[0005] Thermoformable sheet substrates such as PVC are used with
polymeric coated surfaces comprising crosslinked polymers to
provide hard surfaces exhibiting considerably increased durability
to the molded top surface. In the past, coating integrity and
hardness were achieved with various types of crosslinked polymers
to form a tough polymer network, which worked well with flat
surfaces. However, highly crosslinked polymeric coatings have
limited extensibility and elasticity and consequently cannot be
thermoformed into contours and configurations without cracking and
similar coating integrity failure, which ordinarily occur during
the thermoforming process. These thermoforming processes utilize a
thermoformable substrate such as poly(vinyl chloride) surface
coated with a polymeric coating which thermosets while
thermoforming into a desired configuration. For these kinds of
applications, traditional thermoset films fail. Hence, it would be
highly desirable to have a crosslinked coating system for coating
thermoformable sheet substrates with sufficient coating integrity
and extensibility to adhere to the PVC substrate, while exhibiting
sufficient flexibility to maintain coating film integrity during
the subsequent thermoforming process.
[0006] Melamine crosslinked polyester coatings are commonly used in
low and high pressure laminates having flat surfaces. High pressure
laminates typically consist of a multi-layer paper impregnated with
melamine based coatings, where the impregnated laminate is cured at
relatively high temperature and pressure to produce a finished
article having a hard and durable surface. For instance, U.S. Pat.
No. 4,603,074 discloses a plasticized PVC polymer layer having a
polymeric surface coating comprising a reactive carboxyl functional
polyester crosslinked with alkylated benzoguanamine, urea or
melamine formaldehyde resin. The PVC can be printed and/or embossed
prior to application of the polymeric surface coating, but the
cured coating lacks flexibility and is not extensible and cracks
during the thermoforming process. Similarly, U.S. Pat. No.
6,033,737 teaches plasticized PVC sheet substrate having a surface
coating comprising a water-based polyester crosslinked with amino
resin activated by an acid catalyst.
[0007] U.S. Pat. No. 5,650,483 describes the preparation of oxetane
monomers useful to form oxetane polymers with pendant fluorinated
chains. The oxetane polymers in this patent are characterized as
having low surface energy, high hydrophobicity, oleophobicity and a
low coefficient of friction. That patent is incorporated by
reference herein for teachings on how to prepare the oxetane
monomers and polymers. Additional patents issued on variations of
the oxetane monomers and polymers are as follows: U.S. Pat. Nos.
5,468,841; 5,654,450; 5,663,289; 5,668,250, and 5,668,251, all of
which are also incorporated herein by reference.
SUMMARY OF THE INVENTION
[0008] It has been found that a fluorinated polyoxetane modified
polyester polymer adapted to be crosslinked with an alkyl
etherified melamine formaldehyde will provide a polymeric surface
coating suitable for application to a substrate such as PVC and can
be cured in generally two stages comprising, a first low
temperature stage to form a partially cured thermoformable
polymeric layer applied to the PVC substrate, and a second higher
temperature stage in conjunction with thermoforming the
thermoformable layer and the PVC substrate into a desired
configuration, where the applied surface coating is more fully
cured and forms a hard surface coating. The two stage reactive
etherified melamine formaldehyde crosslinking component produces a
thermoformable laminate of partially cured tack free thermoformable
surface coating in the first stage, and a cured, hard coating in
the second stage with the applied and cured laminate residing on a
contoured article.
[0009] In accordance with the present invention, a thermoformable
surface coating for application to a thermoformable substrate, such
as a plastic sheet, and subsequent thermoforming into a desired
configuration is based on a polymeric coating comprising a reactive
fluorinated polyoxetane-polyester polymer adapted to be cured with
an alkyl etherified melamine formaldehyde. The alkyl etherified
melamine formaldehyde can have two different lower alkyl groups
etherified with available methylol groups on the melamine
formaldehyde molecule. In the first stage, low temperature drying
and curing at temperatures up to about 180.degree. F. (82.degree.
C.) provides a partially cured thermoformable coating adhered to
the thermoformable substrate. In the second thermoforming stage,
the thermoformable coating is further cured at higher temperatures
to conform the coated substrate to the desired configuration and
provide a hard surface coating. The fluorinated
polyoxetane-polyester polymer comprises minor amounts of hydroxy
terminated polyoxetane copolymerized polyester reactants to provide
a polyester containing from about 0.1% to about 10% by weight
copolymerized fluorinated polyoxetane in the fluorinated
polyoxetane-polyester polymer. The reactive thermoformable coating
of this invention preferably comprises on a weight basis from about
10% to 80% alkyl etherified melamine formaldehyde with the balance
20% to 90% being fluorinated polyoxetane-polyester polymer on a
total resin weight basis.
[0010] In a further embodiment of the invention, it has been found
that a coating having suitable properties for certain applications
and for the above mentioned multi stage process, can be made as
described above except that the polyester polymer contains
relatively small amounts of and is substantially free or completely
free of any fluorinated polyoxetane component.
[0011] Thus, it has been found that a polyester polymer may be
crosslinked with an alkyl etherified melamine formaldehyde to
provide a polymeric surface coating suitable for application to a
thermoformable substrate such as PVC and wherein the coating is
partially cured to a tack free surface and subsequently cured and
thermoformed to a three dimensional or contoured surface. The
substantially polyoxetane free polyester can be cured in generally
a two step process comprising a first low temperature stage to form
a partially cured thermoformable polymeric coating layer applied to
a polymer thus forming a laminate, and a second higher temperature
stage including thermoforming the laminate into a desired
configuration, for example a three-dimensional configuration,
wherein the alkyl etherified melamine formaldehyde and polyester
mixture is more fully cured and crosslinked and forms a hard
surface coating.
[0012] The coating is based on a polymeric coating comprising a
polyester polymer cured with an alkyl etherified melamine
formaldehyde. The alkyl etherified melamine formaldehyde can have
one or more lower alkyl groups or etherfied substituents having
from 1 to 6 carbon atoms such as methylol and/or butylol groups. As
with the prior embodiment, in the first stage, low temperature
drying and curing at temperatures up to about 180.degree. F.
(82.degree. C.) provides a partially cured thermoformable coating
adhered to the thermoformable substrate. In the second stage, the
thermoformable coating is conformed to the surface of the article
to be coated and subsequently the coating is cured or crosslinked
at higher temperatures. The polyester-melamine reaction mixture is
substantially free of any fluorinated polyoxetane.
DETAILED DESCRIPTION OF THE INVENTION
[0013] The thermoformable coating composition of this invention
comprises an alkyl etherified melamine formaldehyde crosslinking
agent and a reactive fluorinated polyoxetane-polyester polymer
which when partially cured forms a thermoformable coating layer
which can be thermoformed. The polyoxetane-polyester is generally a
block copolymer, and the curing generally occurs in two stages.
[0014] In accordance with a first embodiment of the invention,
modified amino resins comprising a lower alkyl etherified melamine
formaldehyde resin are utilized as crosslinking resins for the
fluorinated polyoxetane-polyester polymer, and also to crosslink
the polyester in the second embodiment of the invention. The
etherified melamine formaldehyde resin is generally etherified with
one or more alkyl groups derived from an alkyl alcohol set forth
hereinbelow. Preferred alkyl etherified melamine formaldehyde
resins comprise mixed alkyl groups in the same melamine
formaldehyde molecule. Mixed alkyl groups comprise at least two
different alkyl groups, for example, methyl and butyl. Useful alkyl
groups comprise lower alkyl chains of 1 to about 6 carbon atoms
where 1 to about 4 carbon atoms are preferred. Preferred mixed
alkyl groups comprise at least two alkyl chains having a
differential of at least two carbon atoms such as methyl/propyl,
and preferably a three carbon atom differential such as
methyl/butyl.
[0015] Melamine formaldehyde molecules ordinarily comprise a
melamine molecule alkylated with at least three formaldehyde
molecules and more typically alkylated with four or five
formaldehyde groups, while most typically fully alkylated with six
formaldehyde groups to yield methanol groups, e.g.
hexamethylolmelamine. In accordance with this invention, at least
two, desirably three or four, and preferably five or six of the
methanol groups are etherified. A melamine formaldehyde molecule
can contain mixed alkyl chains etherified along with one or more
non-etherified methanol groups (known as methylol groups), although
fully etherified groups are preferred to provide essentially six
etherified alkyl groups. Some of the melamine formaldehyde
molecules in a melamine formaldehyde can be non-alkylated with
formaldehyde (i.e. iminom radicals), but preferably minimal to
avoid undesirable rapid premature curing and to maintain controlled
two-stage crosslinking in accordance with this invention.
[0016] Mixed alkyl etherified melamine formaldehyde crosslinking
resins used in this invention can be produced in much the same way
as conventional mono-alkyl etherified melamine formaldehyde is
produced where subsequently all or most methylol groups are
etherified, such as in hexamethyoxymethylmelamine (HMMM). A mixed
alkyl etherified melamine formaldehyde can be produced by step-wise
addition of two different lower alkyl alcohols or by simultaneous
coetherification of both alcohols, with step-wise etherification
being preferred. Typically lesser equivalents of the first
etherified alcohol relative to the available methylol equivalents
of melamine formaldehyde are utilized in the first step to assure
deficient reaction of alkyl alcohol with available formaldehyde
groups, while excess equivalents of the second alcohol are reacted
relative to remaining equivalents of formaldehyde in the second
step to enable full or nearly full etherification with both
alcohols. In either or both alcohol etherification steps, reaction
water can be removed by distillation, or by vacuum if necessary, to
assure the extent of coetherification desired. A preferred
commercial mixed alkyl etherified melamine formaldehyde is Resimene
CE-7103, sold by Solutia comprising mixed methyl and butyl alcohol
etherified with melamine formaldehyde. The preferred mixed alkyl
etherified melamine formaldehyde exhibits temperature sensitive
curing where reactivity is in two stages to provide a partially
cured thermoformable laminate which can be more fully or fully
cured at higher temperatures to provide hard surfaces.
[0017] In accordance with the first embodiment of this invention,
the fluorinated polyoxetane-polyester, (i.e. the "polyFOX" modified
polyester) polymer which generally is a block copolymer contains a
preformed fluorine modified polyoxetane having terminal hydroxyl
groups. Hydroxyl terminated polyoxetane prepolymers comprise
polymerized repeat units of an oxetane monomer having a pendant
--CH.sub.2--O--(CH.sub.2).su- b.n--Rf group prepared from the
polymerization of oxetane monomer with fluorinated side chains.
These polyoxetanes can be prepared in a manner as set forth herein
below, and also according to the teachings of U.S. Pat. Nos.
5,650,483; 5,668,250; 5,688,251; and 5,663,289, hereby fully
incorporated by reference. The oxetane monomer desirably has the
structure 1
[0018] wherein n is an integer from 1 to 5, preferably from 1 to 3,
and Rf, independently, on each monomer is a linear or branched,
preferably saturated alkyl group of from about 1 to about 20,
preferably from about 2 to about 10 carbon atoms with a minimum of
25%, 50%, 75%, 85%, or 95%, or preferably 100% perfluorinated with
the H atoms of said Rf being replaced by F, R being H or an alkyl
of 1 to 6 carbon atoms. The polyoxetane prepolymer can be an
oligomer, a homopolymer, or a copolymer.
[0019] The repeating units from said oxetane monomers desirably
have the structure 2
[0020] where n, Rf, and R are as described above. The degree of
polymerization of the fluorinated oxetane can be from 6 to 100,
advantageously from 10 to 50, and preferably 15 to 25 to produce a
partially fluorinated polyoxetane prepolymer.
[0021] The hydroxyl terminated polyoxetane prepolymer comprising
repeat units of copolymerized oxetane monomers ordinarily have two
terminal hydroxyl groups. Useful polyoxetanes desirably have number
average molecular weights from about 100, 250, 500, 1,000 or 5,000
to about 50,000 or 100,000, and can be a homopolymer or a copolymer
of two or more different oxetane monomers. The polyoxetane
prepolymer may be a copolymer including very minor amounts of
non-fluorinated cyclic ether molecules having from 2 to 4 carbon
atoms in the ring such as tetrahydrofuran and one or more oxetane
monomers as described in the previously incorporated U.S. Pat. No.
5,668,250. Such a copolymer may also include very minor amounts of
copolymerizable substituted cyclic ethers such as substituted
tetrahydrofuran. The repeat unit from a tetrahydrofuran monomer has
the formula --(O--CH.sub.2--CH.sub.2--CH.sub.2--CH.sub.2--). In
some embodiments, the hydroxyl terminated polyoxetane prepolymer
can include from 0% or 0.1% to 10%, advantageously 1% to 5%, and
preferably 2% to 3% copolymerized THF based on the weight of the
preformed hydroxyl terminated polyoxetane copolymer. The preferred
polyoxetane prepolymer contains two terminal hydroxyl groups to be
chemically reacted and bound into the polyoxetane-polyester
polymer.
[0022] The fluorinated polyoxetane-polyester polymers are made by a
condensation polymerization reaction, usually with heat in the
presence of a catalyst, of the preformed fluorinated polyoxetane
with a mixture of at least one dicarboxylic acid or anhydride and a
dihydric alcohol. The resulting fluorinated polyoxetane-polyester
polymer is a statistical polymer and may contain active hydrogen
atoms, e.g., terminal carboxylic acid groups and/or hydroxyl groups
for reaction with the alkyl etherified melamine formaldehyde
crosslinking resin. The ester forming reaction temperatures
generally range from about 110.degree. C. to about 275.degree. C.,
and desirably from about 215.degree. C. to about 250.degree. C. in
the presence of suitable catalysts such as 0.1% dibutyl tin oxide.
Preferred carboxylic acid reactants are dicarboxylic acids and
anhydrides. Examples of useful dicarboxylic acids include adipic
acid, azelaic acid, sebacic acid, cyclohexane dioic acid, succinic
acid, terephthalic acid, isophthalic acid, phthalic anhydride and
acid, and similar aliphatic and aromatic dicarboxylic acids. A
preferred aliphatic dicarboxylic acid is adipic acid and a
preferred dicarboxylic aromatic acid is isophthalic acid.
Generally, the aliphatic carboxylic acids have from about 3 to
about 10 carbon atoms, while aromatic carboxylic acids generally
have from about 8 or 10 to about 25 or 30 carbon atoms.
[0023] Useful polyhydric alcohols generally have from about 2 to
about 20 carbon atoms and 2 or more hydroxyl groups, where diols
are preferred. Examples of useful polyols, especially diols,
include ethylene glycol, propylene glycol, diethylene glycol,
dipropylene glycol, glycerin, butylene glycol, higher alkyl glycols
such as neopentyl glycol, 2,2-dimethyl-1,3-propanediol, and polyols
such as trimethylol propane, 1,4-cyclohexaned imethanol, glycerol
pentaerythritol, trimethylolethane. Mixtures of the polyols and
polycarboxylic acids can be used where diols and dicarboxylic acids
dominate and higher functionality polyols and polyacids are
minimized. An example of a preferred reactive polyester is the
condensation product of trimethylol propane,
2,2-dimethyl-1,3-propane- diol, 1,4-cyclohexanedimethanol,
isophthalic acid or phthalic anhydride, and adipic acid.
[0024] The fluorinated polyoxetane-polyester polymer is made by a
condensation polymerization reaction in the presence of heat and
usually a catalyst with the above noted dicarboxylic acids or
anhydrides and the above noted diols. The polyester component of
the present invention can be formed by reacting the ester forming
reactants in the presence of a preformed intermediate fluorinated
polyoxetane oligomer, polymer, or copolymer to provide an ester
linkage derived from esterifying a dicarboxylic acid or anhydride
with the preformed polyoxetane. Alternatively, a preformed
polyester intermediate can be formed from diols and dicarboxylic
acids, which is then reacted with the preformed fluorinated
polyoxetane oligomer, polymer, or copolymer to form the ester
linkage between the respective preformed components. Thus, block
copolymers are generally formed.
[0025] In preparing the hydroxyl or carboxyl functional
polyoxetane-polyester polymer, it is preferred to pre-react, the
hydroxyl terminated fluorinated polyoxetane oligomer, polymer, or
copolymer, (polyoxetane prepolymer) with dicarboxylic acid or
anhydride to assure copolymerizing the fluorinated polyoxetane
prepolymer into the polyoxetane-polyester polymer via an ester
linkage, which increases the percentage of fluorinated polyoxetane
prepolymer incorporated into the polyoxetane-polyester polymer. A
preferred process to form the ester linkage comprises reacting the
hydroxyl terminated fluorinated polyoxetane prepolymer with excess
equivalents of carboxylic acid from a linear dicarboxylic acid
having from 3 to 10 or 30 carbon atoms such as malonic acid, or
succinic acid, or glutaric acid, or adipic acid, or pimelic acid,
or maleic acid, or fumaric acid, or cyclic cyclohexane dioic acid,
under conditions effective to form a polyoxetane ester intermediate
from the hydroxyl groups of the polyoxetane prepolymer and the
carboxylic acid group of the dicarboxylic acid or anhydride. More
desirably, the excess of carboxylic acid groups is at least 2.05 or
2.1 equivalents reacted with one equivalent of hydroxy terminated
polyoxetane prepolymer to provide a predominantly carboxyl
terminated intermediate prepolymer. The reaction temperature is
generally from about 110.degree. C. to about 275.degree. C. and
desirably from about 215.degree. C. to about 250.degree. C. In the
preferred embodiment for producing the ester intermediate
prepolymer, the amount of other diols are small or zero to force
the carboxylic acid groups to react with the hydroxyl groups of the
fluorinated polyoxetane prepolymer. Desirably, the equivalents of
hydroxyls from other diols are less than 0.5, more desirably less
than 0.2 and preferably less than 0.1 per equivalent of hydroxyls
from the fluorinated polyoxetane prepolymer until after at least
70%, 80%, 90%, or 95% of the hydroxyl groups of the polyoxetane
prepolymer are converted to ester links by reaction with the
dicarboxylic acid.
[0026] The preferred carboxylic acid functional polyoxetane
intermediate can then be reacted with other diol and dicarboxylic
acid reactants to form the polyoxetane-polyester polymer. Although
excess hydroxyl or carboxyl equivalents can be utilized to produce
either hydroxyl or carboxyl functional polyoxetane-polyester
polymer useful in this invention, preferably excess hydroxyl
equivalents are copolymerized to provide a hydroxyl terminated
polyoxetane-polyester polymer. Polyoxetane repeating units are
usually disproportionately present at the surface of the coating
due to the low surface tension of those polymerized units. The
amount of surface fluorine groups can be determined by XPS (x-ray
photoelectron spectroscopy).
[0027] While not as desirable, an alternative route of reacting the
hydroxyl terminated fluorinated polyoxetane oligomer, polymer, or
copolymer (polyoxetane prepolymer) can be reacted directly with a
preformed polyester. In this procedure, the various polyester
forming diols and dicarboxylic acids are first reacted to form a
polyester block which is then reacted with a polyoxetane
prepolymer.
[0028] The amount of fluorinated polyoxetane copolymerized in the
polyoxetane-polyester polymer is desirably from about 0.1% to about
10%, advantageously from about 0.5% to about 5%, and preferably
from 0.5% to about 2% or about 3% by weight based on the weight of
the fluorinated polyoxetane-polyester polymer. If the hydroxyl
terminated polyoxetane prepolymer includes a significant amount of
copolymerized comonomer repeat units from tetrahydrofuran or other
cyclic ether, the hydroxyl terminated polyoxetane prepolymer weight
can exceed the level of copolymerized oxetane repeating units noted
immediately above by the amount of other copolymerized cyclic ether
other than oxetane used to form the polyoxetane copolymer.
[0029] In another embodiment of the invention, the base resin is
the polyester as described hereinabove except that it contains
relatively small amounts, or is substantially free, or is
completely free of any fluorinated polyoxetane block. The amount of
fluorinated polyoxetane therein is generally less than about 2 or
about 1% by weight, desirably less than about 0.5% or about 0.1% by
weight, and preferably completely free of any fluorinated
polyoxetane based upon the total weight of the polyester. The
polyesters which are utilized are the same as set forth hereinabove
and are made in the same manner such as reacting the monomers at
the above indicated reaction temperature in the presence of a
suitable catalyst such as tin oxide and the like. Moreover, the
monomers utilized to form the polyester are the same as set forth
hereinabove and can be aliphatic poly- or di-carboxylic acids
having from 3 to about 10 carbon atoms or aromatic poly- or
di-carboxylic acids having from 8 or 10 to about 25 or 30 carbon
atoms or anhydrides thereof. Examples of useful dicarboxylic acids
include adipic acid, azelaic acid, sebacic acid, cyclohexane dioic
acid, succinic acid, terephthalic acid, isophthalic acid, phthalic
anhydride and acid, and similar aliphatic and aromatic dicarboxylic
acids.
[0030] Useful polyhydric alcohols generally have from about 2 to
about 20 carbon atoms and 2 or more hydroxyl groups, with diols
being preferred. Examples of useful polyols, especially diols,
include ethylene glycol, propylene glycol, diethylene glycol,
dipropylene glycol, glycerin, butylene glycol, higher alkyl glycols
such as neopentyl glycol, 2,2-dimethyl-1,3-propanediol, and polyols
such as trimethylol propane, 1,4-cyclohexanedimethanol, glycerol
pentaerythritol, trimethylolethane. Mixtures of the polyols and
polycarboxylic acids can be used where diols and dicarboxylic acids
dominate and higher functionality polyols and polyacids are
minimized.
[0031] An example of a preferred reactive polyester is the
condensation product of trimethylol propane,
2,2-dimethyl-1,3-propanediol, 1,4-cyclohexanedimethanol,
isophthalic acid or phthalic anhydride, and adipic acid. Another
preferred polyester resin is supplied by Eastman Chemical under the
trade designation 57-5776, which is an oil free polyester polyol
having an equivalent weight of about 315 and a hydroxyl number of
about 178. The polyester of the second embodiment generally has a
number average molecular weight of from about 300 to about 25,000,
desirably from about 500 to about 12,000, and preferably from about
750 or 1,500 to about 2,500 or about 5,000.
[0032] The amount of the various components in the coating will be
generally specified in relationship to 100% by weight of resin
solids of the polyoxetane-polyester or of the polyester resin
polymer and the alkyl etherified melamine formaldehyde. The weight
percent of alkyl etherified melamine formaldehyde crosslinking
agent in the coating is at least 10%, desirably from about 10% to
about 80%, preferably from about 20% to about 70% and most
preferably from about 40% to about 60% by weight of the resin
binder solids of the coating composition of this invention, with
the balance being fluorinated polyoxetane-polyester polymer or in
the second embodiment the polyester polymer.
[0033] The etherified melamine formaldehyde of this invention can
be used with a strong catalyst such as para-toluene sulfonic acid
(PTSA) or methyl sulfonic acid (MSA). Useful acid catalysts can
include boric acid, phosphoric acid, sulfate acid, hypochlorides,
oxalic acid and ammonium salts thereof, sodium or barium ethyl
sulfates, sulfonic acids, and similar acid catalysts. Other
preferred useful catalysts include dodecyl benzene sulfonic acid
(DDBSA), amine blocked alkane sulfonic acid (MCAT 12195), amine
blocked dodecyl para-toluene sulfonic acid (BYK 460), and amine
blocked dodecyl benezene sulfonic acid (Nacure 5543). Ordinarily
from about 1% to about 15% and preferably about 3% to about 10%
acid catalyst is utilized based on polyalkyletherified melamine
formaldehyde and polyester resin used, or in the second embodiment
the polyester polymer.
[0034] The amount of catalyst used is an amount that effectively
catalyzes the mutual partial curing of the polyoxetane-polyester
polymer, or in the second embodiment the polyester polymer, and
alkyl etherified melamine formaldehyde resin in the first stage as
well as second stage curing under conditions chosen at elevated
curing temperatures. In accordance with this invention, the first
stage curing temperature is between about 120.degree. F.
(49.degree. C.) and 170.degree. F. (77.degree. C.) or 180.degree.
F. (82.degree. C.), while the second stage curing temperature is
above 180.degree. F. (82.degree. C.) and preferably between about
190.degree. F. (88.degree. C.) and about 300.degree. F.
(149.degree. C.).
[0035] The amount of carriers and/or solvent(s) in the coating
composition can vary widely depending on the coating viscosity
desired for application purposes, and solubility of the components
in the solvent. The solvent(s) can be any conventional solvent for
polyoxetane-polyester and melamine formaldehyde crosslinker resin
systems. These carriers and/or solvents include ketones of from 3
to 15 carbon atoms e.g. methyl ethyl ketone or methyl isobutyl
ketone, alkylene glycols and/or alkylene glycol alkyl ethers having
from 3 to 20 carbon atoms, acetates and their derivatives, ethylene
carbonate, etc. Suitable alcohol solvents include C.sub.1 to
C.sub.8 monoalcohols such as methyl, ethyl, propyl, butyl alcohols,
as well as cyclic alcohols such as cyclohexanol. Illustrative U.S.
patents of the carrier and/or solvent systems available include
4,603,074; 4,478,907; 4,888,381 and 5,374,691, which are hereby
incorporated by reference for their teachings both of carriers
and/or solvent systems for polyesters. Most acetate type solvents
can be used, e.g. n-butyl acetate, where a preferred solvent is
n-propyl acetate. The amount of solvent(s) can desirably vary from
about 20 parts by weight to about 400 parts by weight per 100 parts
by weight of total polyoxetane-polyester blocks or of the polyester
blocks, and the etherified melamine formaldehyde crosslinker resin
solids.
[0036] Conventional flattening agents can be used in the coating
composition in conventional amounts to control the gloss of the
coating surface to an acceptable value. Examples of conventional
flattening agents include the various waxes, silicas, aluminum
oxide, alpha silica carbide, etc. Amounts desirably vary from about
0 or about 0.1 to about 5 or about 10 parts by weight per 100 parts
by weight total of resin solids of polyoxetane-polyester polymer
and etherified melamine formaldehyde.
[0037] Additionally other conventional additives can be formulated
into the coating composition for particular applications. For
example, polysiloxanes can be used to improve scratch and mar
resistance. This may be particularly advantageous where the
polyester does not include the fluorinated polyoxetane component.
In particular, a suitable polysiloxane can be polyether modified
alkyl polysiloxane, including for example, polyether modified
dimethylpolysiloxane copolymer, such as that sold by BYK-Chemie
under the trade designation BYK-333. Other examples of additives
include viscosity modifiers, antioxidants, antiozonants, processing
aids, pigments, fillers, ultraviolet light absorbers, adhesion
promoters, emulsifiers, dispersants, solvents, crosslinking agents,
etc.
[0038] The thermoformable coatings of this invention can be applied
to thermoformable substrates such as polymers or plastics. Examples
of useful substrates that can be coated with coating compositions
derived from this invention include cellulosic products (coated and
uncoated paper), fibers and synthetic polymers including such as
PVC preferably, or thermoplastic polyester, thermoplastic
polyolefins, alpha olefin polymers and copolymers, polyvinyl
acetate, and poly(meth)acrylates and similar thermoformable
flexible or semi-rigid or rigid substrates. The substrate can be
with or without a backing, with or without printing or embossment
or decoration.
[0039] Intermediate coating(s) known as decorative coatings to
provide a monochromatic or multicolored background or a printed
(patterned) background can be likewise produced in accordance with
this invention. Decorative coatings include designs, flowers,
figures, graphs, maps, etc.
[0040] The thermoformed coated plastic substrate such as PVC also
can be applied to a preformed contoured, i.e., three dimensional,
solid structure or article, such as wood, to form a laminated
article of a high draw or contoured article. Useful articles for
example can be contoured cabinet doors, decorative formed
peripheral edges on flat table tops, and similar contoured
furniture configurations, as well as table tops and side panels,
desks, chairs, counter tops, furniture drawers, hand rails,
moldings, window frames, door panels, and electronic cabinets such
as media centers, speakers, and similar contoured
configurations.
[0041] The cured applied coatings retain film integrity
characteristics free of undesirable cracking while exhibiting
improved extensibility during the thermoforming step and having
significantly improved durability, chemical resistance, stain
resistance, scratch resistance, water stain resistance, and similar
mar resistance characteristics, as well as good surface gloss
control on the fully laminated product.
[0042] The thermoformable substrate film or layer, supported or
unsupported, printed or unprinted, or decorated, single or multiple
colored, can be smooth or embossed to texture the substrate surface
to provide a pattern or design for esthetic or functional purposes.
Embossing of thermoplastic films, layers or sheets is well known
and is usually carried out by passing the film between an embossing
roll and a backup roll under controlled preheating and post-cooling
conditions.
[0043] In accordance with both embodiments of this invention,
controlled generally two stage temperature dependent curing depends
on the softening point of the thermoformable substrate. In
particular, a wet coating is applied to a substrate (e.g. plastic)
and dried to form a composite of dried coating on the substrate.
The composite is then partially cured at low temperatures to form a
thermoformable laminate of partially cured coating adhered to the
substrate. As noted above, the first stage partial curing
temperatures are at web temperatures below 180.degree. F.
(82.degree. C.), desirably between about 120.degree. F. (49.degree.
C.) and about 170.degree. F. (77.degree. C.), and preferably
between about 150.degree. F. (66.degree. C.) and about 160.degree.
F. (71.degree. C.), to form the laminate of partially cured
thermoformable coating adhered to the substrate. Dwell time is
broadly between about 2 seconds and about 60 seconds, preferably
between about 10 seconds and about 20 seconds, depending on the
partial curing temperature. The first stage low temperature partial
curing provides a thermoformable polymeric coating while avoiding
thermosetting crosslinking to form the thermoformable laminate,
which can be thermoformed into any desired contour or shape. The
intermediate thermoformable coating is advantageously extensible
and should exhibit at least about 150% elongation at 180.degree. F.
(82.degree. C.) after the first stage partial curing step.
Generally, partial curing is about 70% to about 80% of the full
cure of a fully cured coating. The resulting thermoformable
laminate is tack free, avoids blocking or inter surface adhesion
between adjacent layers when rolled or stacked in sheets, and
further avoids deformation due to accumulated weight due to rolling
or stacking.
[0044] In the second stage, the thermoformable laminate can then be
applied to the surface or surfaces of a three dimensional article
or structural form with established contours, draws, or
configurations and fully cured at high temperatures above
181.degree. F. (83.degree. C.), and preferably from about
190.degree. F. (88.degree. C.) to about 300.degree. F. (149.degree.
C.) web temperature, to provide a hard, fully cured, crack-free,
mar resistant coating. Dwell time is broadly between about 30
seconds and about five minutes depending on the curing temperature.
The contoured structural article, as noted above, can be a solid
substrate, such as an unfinished contoured desktop which can, for
example, be wood, or wood based composite where the thermoformable
laminate is contoured, thermoset, and adhered directly to the
contoured solid article. Alternatively, the form can be a mold for
forming a free standing thermoset contoured laminate adapted to be
adhered subsequently to an unfinished contoured article. The fully
cured surface exhibits considerable mar resistance along with other
cured film integrity properties. Cured or fully cured coatings
exhibit MEK resistance of at least about 50 MEK rubs and preferably
at least about 75 MEK rubs. It is readily seen that two stage
step-wise heating can be achieved in two or more multiple heat
curing steps to provide partial curing and full curing in
accordance with this invention. Preferably, the final products are
articles of furniture such as cabinets, desks, chairs, tables,
molding, shelves, doors, or housings such as for appliances, or
electronic components.
[0045] The following examples will serve to illustrate the present
invention in respect to Preparation of Mono and Bis(Fluorooxetane)
Monomers. Various fluorinated oxetane monomers can be made in
accordance with U.S. Pat. Nos. 5,650,483; 5,668,250; 5,668,251; and
5,663,289; which have been fully incorporated by reference. While
the following representative examples relate to the preparation of
specific FOX (fluorooxetane) monomers, other mono or bis FOX
monomers can be prepared in a very similar manner.
EXAMPLE M1
[0046] Preparation of 3-FOX Monomer
3-(2,2,2-Trifluoroethoxymethyl)-3-Meth- yloxetane
[0047] Synthesis of the 3-FOX oxetane monomer is performed as
follows:
[0048] A dispersion of 50 weight percent (2.8 grams, 58.3 mmol)
sodium hydride in mineral oil, was washed twice with hexanes and
suspended in 35 milliliters of dimethylformamide. Then, 5.2 grams
(52 mmol) of trifluoroethanol was added and the mixture was stirred
for 45 minutes. A solution of 10.0 grams (39 mmol) of
3-hydroxymethyl-3-methyloxetane p-toluenesulfonate in 15
milliliters of dimethylformamide was added and the mixture was
heated at 75.degree. C.-85.degree. C. for 20 hours, when .sup.1H
MNR analysis of an aliquot sample showed that the starting
sulfonate had been consumed.
[0049] The mixture was poured into 100 milliliters of ice water and
extracted with 2 volumes of methylene chloride. The combined
organic extracts were washed twice with water, twice with 2 weight
percent aqueous hydrochloric acid, brine, dried over magnesium
sulfate, and evaporated to give 6.5 grams of
3-(2,2,2-trifluoroethoxymethyl)-3-methylo- xetane as an oil
containing less than 1 weight percent dimethyl formamide. The yield
of this product was 90%. The oil was distilled at 30.degree. C. and
0.2 millimeters mercury pressure to give 4.3 grams of analytically
pure 3-FOX, corresponding to a 60% yield. The analyses of the
product were as follows: IR (KBr) 2960-2880, 1360-1080, 990, 840
cm.sup.-1; .sup.1H NMR .delta.1.33 (s, 3H), 3.65 (s, 2H), 3.86 (q,
J=8.8 Hz, 2 H), 4.35 (d, J=5.6 Hz, 2 H), 4.51 (d, J=5.6 Hz, 2 H);
.sup.13C NMR .delta.20.72, 39.74, 68.38 (q, J=40 Hz), 77.63, 79.41,
124 (q, J=272 Hz). The calculated elemental analysis for C.sub.7
H.sub.11F.sub.3O.sub.2 is: C=45.65; H=6.02; F=30.95. The
experimental analysis found: C=45.28; H=5.83; F=30.59.
EXAMPLE M2
[0050]
1 Preparation of 5-FOX Monomer: Ratio Weight Mole Material Scale
Weight (S .times. Ratio) MW Mmoles Ratio Density
pentafluoropropanol 100 1.00 100.00 150.05 666.44 1.00 1.373 BrMMO
1.112 112.18 165.02 679.77 1.02 1.435 TBAB 0.0537 5.37 322.37 16.66
0.025 1 Water 0.385 38.53 18.01 2139.27 3.21 1.000 45% aq. KOH
0.914 91.39 56.10 733.08 1.10 1.180 Water 0.616 61.57 18.01 3418.84
5.13 1.000 45% aq. KOH 0.027 2.66 56.01 21.33 0.032 1.180 Water
0.588 58.81 18.01 3265.56 4.90 1.000 Theoretical Yield (g) 156.1
Expected Yield, low (g) 117.0 Expected Yield, high (g) 148.2 Solids
Loading, % 44.9
[0051] Pentafluoropropanol, BrMMO, Tetrabutyl Ammonium bromide, and
water were added to a 500 ml round bottomed flask equipped with a
magnetic stirrer, thermometer, and addition funnel. The reactor was
heated to 85.degree. C., and 45% aqueous potassium hydroxide was
added over 1 hour. The reactor was allowed to stir for an
additional 4 hours. A 2-phase reaction mixture with a light yellow
organic phase resulted. The reaction mixture was poured into a
separatory funnel where the aqueous phase was removed. The organic
layer was separated and washed with 45% potassium hydroxide, and
deionized water. 152.31 grams of light yellow crude 5-FOX monomer
was isolated. 15.40 grams of hexane was added, and the mixture was
distilled. Low boilers distilled at 55.degree. C.-60.degree. C. at
atmospheric pressure. The mixture was slowly subjected to vacuum,
and additional low boilers were collected below 70.degree. C. The
vacuum was slowly increased, and 5-FOX monomer distilled from
96.degree. C.-102.degree. C. The vacuum was 28 inches of mercury.
133.85 grams of pure 5-FOX monomer was isolated, or 85%. Both
.sup.1H and .sup.13C spectra are consistent with 5-FOX monomer
C.sub.8H.sub.11F.sub.5O.sub.2 molecular weight =234.16.
EXAMPLE M3
[0052] Preparation of 7-FOX Using PTC Process
3-(2,2,3,3,4,4,4-Heptafluoro- butoxymethyl)-3-Methyloxetane:
[0053] A 2 L, 3 necked round bottom flask fitted with a reflux
condenser, a mechanical stirrer, a digital thermometer and an
addition funnel was charged with 3-bromomethyl-3-methyloxetane
(351.5 g, 2.13 mol), heptafluorobutan-1-ol (426.7 g, 2.13 mol),
tetrabutylammonium bromide (34.4 g) and water (85 ml). The mixture
was stirred and heated to 75.degree. C. Next, a solution of
potassium hydroxide (158 g, 87% pure, 2.45 mol) in water (200 ml)
was added and the mixture was stirred vigorously at
80.degree.-85.degree. C. for 4 hours. The progress of the reaction
was monitored by GLC and when GLC analysis revealed that the
starting materials were consumed, the heat was removed and the
mixture was cooled to room temperature. The reaction mixture was
diluted with water and the organic layer was separated and washed
with water, dried and filtered to give 566 g (94%) of crude
product. The crude product was transferred to a distillation flask
fitted with a 6 inch column and distilled as follows:
[0054] Fraction #1, boiling between 20.degree. C.-23.degree. C./10
mm-Hg, was found to be a mixture of heptafluorobutanol and other
low boiling impurities, was discarded;
[0055] Fraction #2, boiling between 23.degree. C. and 75.degree.
C./1 mm-Hg, was found to be a mixture of heptafluorobutanol and
7-FOX, was also discarded; and
[0056] Fraction #3, boiling at 75.degree. C./1 mm-Hg was >99%
pure 7-FOX representing an overall yield of 80.2%
[0057] NMR and GLC data revealed that 7-FOX produced by this method
was identical to 7-FOX prepared using the sodium hydride/DMF
process.
EXAMPLE M4
[0058] Preparation of
3,3-bis(2,2,2-trifluroethoxymethyl)oxetane(B3-FOX):
[0059] Sodium hydride (50% dispersion in mineral oil, 18.4 g, 0.383
mol) was washed with hexanes (2.times.) and was suspended in DMF
(200 mL). Then trifluoroethanol (38.3 g, 0.383 mol) was added
dropwise over 45 min while hydrogen gas was evolved. The mixture
was stirred for 30 min and a solution of
3,3-bis-(hydroxymethyl)oxetane di-p-toluenesulfonate (30.0 g, 0.073
mol) in DMF (50 mL) was added. The mixture was heated to 75.degree.
C. for 64 h when .sup.1H NMR analysis of an aliquot showed that the
starting sulfonate had been consumed. The mixture was poured into
water and extracted with methylene chloride (2.times.). The
combined organic extracts were washed with brine, 2% aqueous HCl,
water, dried (MgSO4), and evaporated to give 17.5 g (100%) of
3,3-bis-(2,2,2-trifluoroethoxymet- hyl)oxetane as an oil containing
DMF (<1%). The oil was purified by bulb-to-bulb distillation at
42.degree. C.-48.degree. C. (10.1 mm) to give 15.6 g (79%) of
analytically pure B3-FOX, colorless oil: IR (KBr) 2960-2880,
1360-1080, 995, 840 cm.sup.-1; .sup.1H NMR .delta.3.87 (s 4H), 3.87
(q,J=8.8 Hz, 4H), 4.46 (s, 4H); .sup.13C NMR .delta.43.69, 68.62
(q,J=35 Hz), 73.15, 75.59, 123.87 (q,J=275 Hz); .sup.19F NMR
.delta.74.6(s). Anal. Calcd, for C.sub.9H.sub.12F.sub.6O.sub.3;
C,38.31;H, 4.29; F, 40.40. Found: C, 38.30; H, 4.30; F, 40.19.
[0060] Preparation of oligomers, polymers or copolymers from the
fluorinated oxetane monomers described herein can be made in
accordance with U.S. Pat. Nos. 5,650,483; 5,668,250; 5,668251; or
5,663,289; hereby fully incorporated by reference.
[0061] The following examples demonstrate the merits of this
invention.
EXAMPLE 1
[0062] An example of preparing a poly-FOX-THF copolymer is as
follows:
[0063] A 10 L jacketed reaction vessel with a condenser,
thermo-couple probe, and a mechanical stirrer was charged with
anhydrous methylene chloride (2.8 L), and 1,4-butanediol (101.5 g,
1.13 moles). BF.sub.3THF (47.96 g, 0.343 moles) was then added, and
the mixture was stirred for 10 minutes. A solution of 3-Fox,
3-(2,2,2-trifluoroethoxyl-methyl)-3-methylo- xetane, made in
accordance with U.S. Pat. Nos. 5,650,483; 5,668,250; 5,663,289; or
5,668251, (3,896 g. 21.17 moles) in anhydrous methylene chloride
(1.5 L) was then pumped into the vessel over 5 hours. The reaction
temperature was maintained between 38.degree. C. and 42.degree. C.
throughout the addition. The mixture was then stirred at reflux for
an additional 2 hours, after which .sup.1H NMR indicated >98%
conversion. The reaction was quenched with 10% aqueous sodium
bicarbonate (1 L), and the organic phase was washed with 3% aq. HCl
(4 L) and with water (4 L). The organic phase was dried over sodium
sulfate, filtered, and stripped of solvent under reduced pressure
to give 3,646 g (91.2%) of title glycol, a clear oil. NMR: The
degree of polymerization (DP) as determined by TFAA analysis was
15.2 which translates to an equivalent weight of 2804. The THF
content of this glycol, as determined by 1 H NMR, was 2.5% wt THF
(6.2% mole THF). This example was included to teach how to
polymerize partially fluorinated oxetane polymers.
EXAMPLE 2
[0064]
2 Synthesis of Poly-5-FOX-THF Copolymer at a DP of 20 Weight (S
.times. Ratio) Mole Compound Scale Ratio G MW Moles Ratio .delta.
ml 5-FOX Monomer.sup.(1) 979.3 1.0 979.250 234.16 4.18 50.05 1.150
851.5 THF 0 0.000 72.10 0.00 0.00 0.886 0.0 Methylene Chloride 0.53
519.003 84.93 6.11 73.14 1.330 390.2 Neopentyl glycol 0.02222
21.756 104.15 0.21 2.50 1.017 21.4 BF.sub.3THF 0.01194 11.689
139.90 0.08 1.00 1.268 9.2 Methylene Chloride 0.8 783.400 84.93
9.22 110.40 1.330 589.0 5% sodium bicarbonate 0.43 421.078 18.01
23.38 279.82 1.000 421.1 Water 0.85 832.363 18.01 46.22 553.13
1.000 832.4 Theoretical Yield (g) 1007.03 Expected Yield, Low (g)
906.33 Expected Yield, High (g) 956.68 Solids Loading, % 63.93 Max.
Wt % BF.sub.3THF 1.16 (incorporated as THF) ml Initial Volume
1272.36 Volume after quench, ml 2282.46 Volume after wash, ml
2693.75 .sup.(1)5-FOX Monomer is oxetane with a pendant
--CH.sub.2--O--CH.sub.2--CF.sub.2--CF.sub.3 and molecular weight of
234.16.
[0065] Methylene chloride (1019.003 grams, 11.99 moles, 766.17 ml)
was charged to a 4 liter jacketed reaction vessel equipped with a
reflux condenser, mechanical stirrer, temperature probe, monomer
addition pump, and jacket temperature control. Neopentyl glycol
(21.756 grams, 0.21 moles) and BF.sub.3THF (11.689 grams, 0.08
moles) were charged to the reactor with a temperature of 25.degree.
C. The neopentyl glycol dissolved upon addition of BF.sub.3THF. The
reaction was allowed to stir for 30 minutes. 5-FOX monomer addition
was commenced with a reaction temperature of 25.degree. C., and a
reaction exotherm was observed within 5 minutes. Once the exotherm
started, 5-FOX monomer was added over 75 minutes. The maximum
temperature observed was 36.3.degree. C. After complete addition of
the monomer, the reaction mixture was heated to 35.degree. C. for 4
hours. A sample was taken and analyzed by NMR, and a degree of
polymerization of 21.35 was observed. Additional methylene chloride
was added (283.4 grams, 213.08 ml). The reaction mixture was
neutralized with 5% sodium bicarbonate solution (421.078, 21.0539
grams sodium bicarbonate, 0.2506 moles). The methylene
chloride-polymer layer was then washed with deionized water
(832.363 grams). A pH of 7 was observed. The water phase was
separated. The polymer phase is distilled under reduced pressure to
remove methylene chloride and dry the polymer.
[0066] About 963.61 grams of poly-5-FOX-THF Copolymer DP 21.35 were
isolated.
EXAMPLE 3
[0067]
3 Synthesis of Poly-3-FOX-co-Poly-Elf-FOX 25% Substance Scale (g)
Ratio Quantity (g) MW Eq Mmoles .delta. ml Elf FOX Monomer.sup.(1)
3500 0.490577 1,717.02 532 5.00 3,227.48 1.4 1226.4 3-FOX
Monomer.sup.(2) 0.509425 1,782.99 184.15 15.00 9,682.26 1.15 1550.4
Neopentyl Glycol 0.0191986 67.20 104.1 1.00 645.49 1.06 63.4
Heloxy7 0.0420488 147.17 228 1.00 645.49 0.91 161.73 BF.sub.3THF
0.00806 28.21 139.9 0.31 201.64 1.1 25.6 Oxsol 2000 0.57 1,995.00
146.11 21.15 13,654.10 1.185 1683.5 CH.sub.2Cl.sub.2 0.205 717.50
84.93 13.09 8,448.13 1.326 541.1 Quench (water) 2,576.97 18.01
221.67 143,085.52 1.00 2577.0 Wash (water) 2,576.97 18.01 221.67
143,085.52 1.00 2577.0 Theoretical Yield (g) 3,728.91 Expected
Yield, 3,542.47 (95%) Solids Loading, (%) 72.35% ml Initial Volume
5,153.94 Volume + Quench 7,730.91 Volume + Wash 7,730.91
.sup.(1)Poly Elf FOX Monomer is oxetane with mixed pendant
fluorinated C.sub.4-C.sub.16 alcohols from ALF Actochem
.sup.(2)3-FOX Monomer is oxetane with a pendant Rf = CF.sub.3.
[0068] Methylene chloride (717.50 grams, 8.45 moles, 541.1 ml) was
charged to a 10 liter jacketed reaction vessel equipped with a
reflux condenser, mechanical stirrer, temperature probe, monomer
addition pump, and jacket temperature control. Neopentyl glycol
(67.20 grams, 0.645 moles) and BF.sub.3THF (28.21 grams, 0.201
moles) were charged to the reactor with a temperature of 25.degree.
C. The neopentyl glycol dissolved upon addition of BF.sub.3THF. The
reaction was allowed to stir for 30 minutes. A solution of Elf-FOX
monomer (1717.02 grams, 3.227 moles, 1226.4 ml), 3-FOX monomer
(1,782.99 grams, 9.682 moles, 1550.4 ml), and Heloxy 7 (147.17
grams, 0.645 moles, 161.73 ml) in Oxsol 2000 (1995.00 grams, 1683.5
ml) was prepared. Addition of the monomer solution was commenced
with a reaction temperature of 25.degree. C., and a reaction
exotherm was observed within 7 minutes. Once the exotherm started,
monomer was added over 1 hour 55 minutes. The maximum temperature
observed was 40.0.degree. C. After complete addition of the
monomer, the reaction mixture was heated to 35.degree. C. for 4
hours. A sample was taken and analyzed by NMR, and a total FOX
degree of polymerization of 18.67 was observed. The reaction
mixture was neutralized with 5% sodium bicarbonate solution
(2576.97 grams, 128.85 grams sodium bicarbonate, 1.53 moles). The
methylene chloride-polymer layer was then washed with deionized
water (2576 grams). A pH of 7 was observed. The water phase was
separated. The polymer phase is distilled under reduced pressure to
remove methylene chloride and dry the polymer. 3632.4 grams of
poly-3-FOX-co-Elf-FOX 25% DP 18.67 was isolated. Final
characterization showed 23.5% Elf-FOX, and a hydroxyl equivalent
weight of 2640.6.
EXAMPLE 4
[0069] Synthesis of Poly-3-FOX-Z 10 Copolymer
[0070] An oxetane copolymer was produced in the same manner as
described in Example 3 except the weight ratio of monomers was 90%
3-FOX monomer and 10% Z 10 monomer produced by DuPont. Z10 monomer
is an oxetane monomer with mixed pendant fluorinated alkyl alcohol
chains.
EXAMPLE 5
[0071] Synthesis of Fluorinated Polyoxetane-Polyester Polymer
Blocks
[0072] Two different hydroxyl terminated fluorinated polyoxetanes
were used to prepare different polyoxetane-polyester polymers
according to this invention. The first polyoxetane had 6 mole
percent repeating units from tetrahydrofuran (THF) with the rest of
the polymer being initiator fragment and repeating units form 3-FOX
where n=1, Rf is CF.sub.3, and R is CH.sub.3. The number average
molecular weight of the first polyoxetane was 3400. The second
polyoxetane had 26 mole percent of its repeating units from
tetrahydrofuran with the residual being the initiator fragment and
repeating units from 3-FOX. 3-FOX is also known as
3-(2,2,2-trifluoroethoxylmethyl)-3-methyloxetane.
[0073] The first and second fluorinated oxetane polymers were
reacted with at least a 2 equivalent excess (generally 2.05-2.10
excess) of adipic acid in a reactor at 455.degree. F. for 3.5 hours
to form a polyoxetane having the half ester of adipic acid as
carboxyl end groups. The preformed ester linkage and terminal
carboxyl groups will chemical bond the polyoxetane to a
subsequently in-situ formed polyester. NMR analysis was used to
confirm that substantially all the hydroxyl groups on the
polyoxetane were converted to the ester groups. The average degree
of polymerization of the first oxetane polymer was reduced from 18
to 14 during the reaction with adipic acid. The average degree of
polymerizations of the second oxetane polymer remained at 18
throughout the reaction. The reactants were then cooled to
300.degree. F.
[0074] The adipic acid functionalized polyoxetane was then reacted
with additional diacids and diols to form polyester blocks. The
diacids were used in amounts of 24.2 parts by weight of adipic acid
and 24.5 parts by weight of isophthalic acid or phthalate
anhydride. The diols were used in amounts of 20.5 parts by weight
of cyclohexanedimethanol, 14.8 parts by weight neopentyl glycol,
and 16.0 parts by weight trimethylol propane. The relative amounts
of the adipate ester of the oxetane polymer and the polyester
forming components were adjusted to result in
polyoxetane-polyesters with either 2 or 4 weight percent of
partially fluorinated oxetane repeating units. The diacid and diol
reactants were reacted in the same reactor used to form the
carboxyl functional polyoxetane but the reaction temperature was
lowered to 420.degree. F. The reaction to form the
polyoxetane-polyester polymer was continued until the calculated
amount of water was generated. The finished batch sizes were from
20 to 30 gallons.
[0075] The resulting polyoxetane-polyester polymer was formulated
into coating compositions according to "Coating Preparation" set
forth hereinafter. The polyoxetane-polyester polymers were mixed
with an alkyl etherified melamine formaldehyde resin Resimene
CE-7103, a highly monomeric, methyl/butyl etherified melamine
formaldehyde sold by Solutia.
COATING PREPARATION AND TESTING
Coating Preparation for the First Embodiment
[0076] Flurorinated polyoxetane-polyester polymer was mixed with
Resimene CE-7103 methyl/butyl etherified melamine formaldehyde
crosslinking agent. The poly 5-FOX-polyester polymer is made from a
poly-5-FOX polymer as made in example 2 and is reacted with adipic
acid to form an ester linkage having a terminal carboxyl group and
subsequently reacted with ester forming monomers in a manner
substantially as set forth in Example 5 wherein the acids are
adipic acid and phthalate anhydride.
4 1. A highly monomeric, methyl/butyl etherified 31.4 pph melamine
formaldehyde resin. (Solutia, Resimene CE-7103) 2.
Poly-5-FOX-Polyester Polymer 31.4 pph 3. N-propyl acetate 20.7 pph
4. Tetrahydrofuran 3.5 pph 5. Isopropyl alcohol 6.0 pph 6.
Para-toluene sulfonic acid 4.0 pph 7. Polyether modified
dimethylpolysiloxane 0.7 pph copolymer (Byk-Chemie BYK-333) 8.
Fumed silica (Degussa TS100) 1.4 pph 9. Micronized fluorocarbon wax
0.9 pph (Micropowders Polyfluo 190)
[0077] The polyether modified dimethylpolysiloxane copolymer (BYK
333) was added to improve scratch and mar resistance.
[0078] The fumed silica (Degussa TS100) was added to control the
coating gloss.
[0079] The micronized fluorocarbon wax was added to improve scratch
and mar resistance.
Laminate Preparation
[0080] Coatings were applied to PVC substrate sheets with a gravure
coater and dried in a forced air oven and then partially cured at
150.degree. F. to 160.degree. F. for 10 to 20 seconds to form a
partially cured thermoformable coating film. Coating weights were
6-8 grams/square meter of substrate. The PVC substrate was 0.012
inch thick with a lightly embossed surface (E13 embossing).
Thermoforming and Curing Procedure
[0081] The coated samples were thermoformed to MDF wood board using
a Greco membrane press. The press cycle is described below.
[0082] 1. Coated PVC is placed over a MDF board
[0083] 2. Flexible membrane is laid over PVC film and MDF board
[0084] 3. The membrane is heated to 280.degree. F. (138.degree. C.)
to thermoform and cure
[0085] 4. A vacuum pulls the membrane tightly around PVC film and
MDF board (thermoforming). Heat is maintained for 1 minute
[0086] 5. Heat is removed and membrane is allowed to cool for 1
minute while vacuum is maintained
[0087] 6. After 1 minute cooling, vacuum is released and sample is
removed
[0088] 7. Maximum surface temperature of PVC is measured and
recorded with a temperature indicating tape.
[0089] The following test procedures were used to measure coating
durability (resistance to coating cracking).
Scratch Resistance
[0090] Scratch resistance was measured with a "Balance Beam Scrape
Adhesion and Mar Tester" that is manufactured by the Paul N.
Gardner Company, Inc. A. Hoffman stylus was used to scratch the
coatings. The scratch resistance is the high stylus load the
coating can withstand without scratching.
Burnish Mar
[0091] Mar resistance was determined by firmly rubbing a polished
porcelain pestle on the coating surface. The severity of a mark is
visually assessed as:
5 Severe: mark is visible at all angles Moderate: mark is visible
at some angles Slight: mark is visible only at grazing angles None:
no perceivable mark
Solvent Resistance (MEK double rubs)
[0092] A cloth towel was soaked with MEK and gently rubbed on the
coated surface in a back and forth manner. One back and forth
movement was counted as one rub. The coated surface was rubbed
until a break in the coating surface first became visible. The test
is stopped after 100 double-rubs.
Coating Crack
[0093] After thermoforming the coated PVC films to molded MDF
parts, the corners and edges were visually inspected for coating
cracks.
Cleanability/Stain
[0094] Stain resistance was measured by common household substances
published by NEMA Standards Publications LD-3 for High Pressure
Decorative Laminates. The method consists of placing a spot of each
test reagent i.e. distilled water, acetone, household ammonia,
critic acid solution, olive oil, tea, coffee, mustard, providone
iodine, stamp ink, #2 pencil, wax crayon, and shoe polish, upon the
flat surface of the laminated PVC. The samples were undisturbed for
16 hours and after that the stain reactants were cleaned with
different stain removers that are commonly used as commercial
cleaners (i.e. 409, Fantastik), baking soda, nail remover, and
finally bleach. Depending on the stain severity (high values) or
ease (low values) of its removal, the total value from each test
sample was determined.
6TABLE 1 Stain Remover Values Cleaner - Remover Grade Water 0
Commercial Cleaner 1 Commercial cleaner + baking soda 2 Nail Polish
Remover 3 5.0% solution of sodium hypochlorite (bleach) 4
COATED SUBSTRATE VERSUS UNCOATED SUBSTRATE
[0095]
7TABLE 2 Durability Testing COATED + COATED THERMOFORMED AND AND
PARTIALLY PROPERTIES CURED CURED UNCOATED Hoffman Scratch 2050 g
1850 g 1000 g Burnish Mar Slight Slight Moderate MEK double rub 90
rubs 60 rubs 4 rubs Coating crack None None None
[0096]
8TABLE 3 NEMA Stain Test Results (Coated + Thermoformed and Cured)
Stain remover values from Table 1 were used below in a progressing
intensity stain removing test scale, where 0 = water 1 = commercial
cleaner 2 = commercial cleaner and baking soda 3 = Nail polish
remover 4 = Solution 5% of sodium hypochlorite (bleach) A "1" in
the test result indicates the stain was not removed until a
stronger stain remover was used. Cleaning reagents Test Material 0
1 2 3 4 Score Stain Distilled Water 50/50: Distilled Water/ Ethyl
Alcohol Acetone 1 1 1 1 1 5 Moderate Household Ammonia Citric Acid
Vegetable Cooking Oil Coffee Tea 1 1 Catsup Mustard 1 1 1 3 10%
Povidone Iodine 1 1 Permanent Marker 1 1 1 3 #2 Pencil 1 1 Wax
Crayon 1 1 Shoe Polish 1 1 Total 16
[0097]
9TABLE 4 NEMA Stain Results (Coated and Partially Cured) Cleaning
reagents Test Material 0 1 2 3 4 Score Stain Distilled Water 50/50:
Distilled Water/ Ethyl Alcohol Acetone 1 1 1 1 1 5 Moderate
Household Ammonia Citric Acid Vegetable Cooking Oil Coffee Tea 1 1
Catsup Mustard 1 1 2 10% Povidone Iodine Permanent Marker 1 1 1 3
#2 Pencil 1 1 Wax Crayon 1 1 Shoe Polish 1 1 Total 14
[0098]
10TABLE 5 NEMA Stain Results (Uncoated PVC) Cleaning reagents Test
Material 0 1 2 3 4 Score Stain Distilled Water 50/50: Distilled
Water/ Ethyl Alcohol Acetone 1 1 1 1 1 5 Moderate Household Ammonia
Citric Acid Vegetable Cooking Oil Coffee 1 1 2 Tea Catsup Mustard 1
1 1 3 10% Povidone Iodine 1 1 Permanent marker 1 1 1 1 1 5 Moderate
#2 Pencil 1 1 2 Wax Crayon 1 1 2 Shoe Polish 1 1 1 3 Total 23
Results
[0099] Coated samples showed significantly greater Hoffman scratch
resistance compared to uncoated PVC. The coated+thermoformed sample
showed a greater Hoffman scratch resistance compared to the coated
sample.
[0100] The burnish resistance of the coated+thermoformed and coated
samples were greater than the uncoated PVC.
[0101] The coated+thermoformed sample withstood 90 MEK double rubs
and the coated sample withstood 60 MEK double rubs. The greater
number of double rubs observed for the coated+thermoformed sample
indicates a greater level of curing or postcured that occurs during
the thermoforming process. After 4 double rubs, the surface of
uncoated PVC began to show streaks.
[0102] The NEMA cleanability score from the thermoformed+coated and
coated sample were 16 and 14, respectively. The uncoated PVC showed
a cleanability score of 19. After cleaning all of the samples
showed a moderate stain from acetone. In addition, the uncoated PVC
showed a moderate stain from a permanent marker.
[0103] Coatings were applied to PVC substrate with a #5 wire wound
rod and dried in a forced air oven and then partially cured at
165.degree. F. for 30 seconds to form a partially cured
thermoformable coating film.
Coating Preparation for the Second Embodiment
[0104] The melamine/polyester coatings presented in the second
embodiment of the disclosure were prepared from the following
formulation.
11 Highly methyl/butyl coetherified melamine 31.4 pph formaldehyde
resin (Solutia, Resimene CE-7103) Polyester Resin 31.4 pph Eastman
Chemical, Polymac 57-5776 or, Omnova Fluorinated Poly-oxetane
polyester (poly 5-FOX-polyester - Examples 2 & 5) N-propyl
acetate 20.7 pph Tetrahydrofuran 3.5 pph Isopropyl alcohol 6.0 pph
Para-toluene sulfonic acid 4.0 pph Polyether modified
dimethylpolysiloxane 0.7 pph copolymer (Byk-Chemie BYK 333) Fumed
silica (Degussa TS100) 1.4 pph Micronized fluorocarbon wax
(Micropowders 0.9 pph Polyfluo 190)
[0105] The polyether modified dimethylpolysiloxane copolymer (BYK
333) was added to improve scratch and mar resistance.
[0106] The fumed silica (Degussa TS100) was added to control the
coating gloss.
[0107] The micronized fluorocarbon wax was added to improve scratch
and mar resistance.
Laminate Preparation
[0108] The coating prepared with the Polymac 57-5776 polyester were
applied to PVC sheets with a #5 wire wound drawdown bar and dried
in a laboratory oven at 150.degree. F. (66.degree. C.) for 30
seconds. The PVC substrate was 0.012 inch thick with a lightly
embossed surface (E13 embossing).
[0109] Coating prepared with the Omnova Fluorinated Poly-oxetane
polyester were applied to PVC sheets with a gravure coater and
dried in a forced air oven at 150.degree. F. (66.degree. C.) for 10
seconds. The PVC substrate was 0.012 inch thick with a lightly
embossed surface (E13 embossing).
Thermoforming and Curing Procedure
[0110] The coated samples were thermoformed to MDF wood board using
a Greco membrane press. The press cycle is described below.
[0111] Coated PVC is placed over a MDF board
[0112] Flexible membrane is laid over PVC film and MDF board
[0113] The membrane is heated to 280.degree. F. (138.degree.
C.)
[0114] A vacuum pulls the membrane tightly around PVC film and MDF
board (thermoforming). Heat is maintained for 1 minute
[0115] Heat is removed and membrane is allowed to cool for 1 minute
while vacuum is maintained
[0116] After 1 minute cooling, vacuum is released and sample is
removed.
[0117] Maximum surface temperature of PVC is measured and recorded
with a temperature indicating tape.
[0118] The following test procedures were used to measured coating
durability
Scratch Resistance
[0119] Scratch resistance was measured with a "Balance Beam Scrape
Adhesion and Mar Tester" that is manufactured by the Paul N.
Gardner Company, Inc.. A Hoffman stylus was used to scratch the
coatings. The scratch resistance given in the table above is the
highest stylus load the coating can withstand with out
scratching.
Burnish Mar
[0120] Mar resistance was determined by firmly rubbing a polished
porcelain pestle on the coating surface. The severity of a mark is
visually assesses as:
12 Severe: mark is visible at all angles Moderate: mark is visible
at some angles Slight: mark is visible only at grazing angles None:
no perceivable mark
Solvent Resistance (MEK double rubs)
[0121] A cloth towel was soaked with methyl ethyl ketone and gently
rubbed on the coated surface in a back and forth manner. One back
and forth movement was counted as one rub. The coated surface was
rubbed until a break in the coating surface first became visible.
The test is stopped after 100 double-rubs even if the coated
surface remains intact.
Coating Crack
[0122] After thermoforming the coated PVC films to molded MDF
parts, the corners and edges were visually inspected for coating
cracks.
Cleanability/Stain
[0123] Stain resistance was measured by common household substances
published by NEMA Standards Publications LD-3 for High Pressure
Decorative Laminates. The method consists of placing place a spot
of each test reagent i.e. distilled water, acetone, household
ammonia, citric acid solution, olive oil, tea, coffee, mustard,
providone iodine, stamp ink, #2 pencil, wax crayon, and shoe
polish, upon the flat surface of the laminated PVC. The samples
were undisturbed for 16 hrs and after that the stain reactants were
cleaned with different stain removers that are commonly used as
commercial cleaners (i.e. 409 Fantastik), baking soda, nail
remover, and finally, bleach. Depending on the stain severity (high
values) or ease (low values) of its removal, the total value from
each test sample was determinated.
13TABLE 6 Stain Remover Values. Cleaner Remover Grade Water 0
Commercial Cleaner 1 Commercial cleaner + baking soda 2 Nail Polish
Removed 3 5.0% solution of sodium hypochlorite (bleach) 4
Physical Test Results
[0124]
14TABLE 7 DURABILITY TESTING Melamine/ Melamine/Fluorinated
Polyester Poly-oxetane Polyester Uncoated PROPERTIES Coating
Coating PVC Hoffman Scratch 3000 g 2050 g 1000 g Burnish Mar None
Slight Moderate MEK double rub 80 90 rubs 4 rubs Coating crack None
None None
[0125] laminated PVC. The samples were undisturbed for 16 hrs and
after that the stain reactants were cleaned with different stain
removers that are commonly used as commercial cleaners (i.e. 409
Fantastik), baking soda, nail remover, and finally, bleach.
Depending on the stain severity (high values) or ease (low values)
of its removal, the total value from each test sample was
determinated.
15TABLE 6 Stain Remover Values. Cleaner Remover Grade Water 0
Commercial Cleaner 1 Commercial cleaner + baking soda 2 Nail Polish
Removed 3 5.0% solution of sodium hypochlorite (bleach) 4
Physical Test Results
[0126]
16TABLE 7 DURABILITY TESTING Melamine/ Melamine/Fluorinated
Polyester Poly-oxetane Polyester Uncoated PROPERTIES Coating
Coating PVC Hoffman Scratch 3000 g 2050 g 1000 g Burnish Mar None
Slight Moderate MEK double rub 80 90 rubs 4 rubs Coating crack None
None None
[0127]
17TABLE 8 NEMA CLEANABILITY/STAIN RESULTS FROM MELAMINE/POLYESTER
COATING Test Material 0 1 2 3 4 SCORE STAIN Distilled Water Ethyl
Alcohol and Water 50/50 Acetone 1 1 1 1 1 5 Moderate Household
Ammonia Citric Acid 10% Vegetable Cooking Oil Coffee Tea 1 1 2
Tomato Catsup Mustard 1 1 1 3 Iodine 10% 1 1 1 3 Permanent Marker 1
1 1 3 #2 Pencil 1 1 Wax Crayon 1 1 Shoe Polish 1 1 2 Total 20
[0128]
18TABLE 9 NEMA CLEANABILITY/STAIN RESULTS FROM MELAMINE/FLUORINATED
POLY-OXETANE POLYESTER COATING Test Material 0 1 2 3 4 SCORE STAIN
Distilled Water Ethyl Alcohol and Water 50/50 Acetone 1 1 1 1 1 5
Moderate Household Ammonia Citric Acid 10% Vegetable Cooking Oil
Coffee Tea 1 1 Tomato Catsup Mustard 1 1 1 3 Iodine 10% 1 1
Permanent Marker 1 1 1 3 #2 Pencil 1 1 Wax Crayon 1 1 Shoe Polish 1
1 Total 16
[0129]
19TABLE 10 NEMA CLEANABILITY/STAIN RESULTS FROM UNCOATED PVC
Cleaning reagents Test Material 0 1 2 3 4 Score Stain Distilled
Water 50/50: Distilled Water/ Ethyl Alcohol Acetone 1 1 1 1 1 5
Moderate Household Ammonia Citric Acid Vegetable Cooking Oil Coffee
1 1 2 Tea Catsup Mustard 1 1 1 3 10% Povidone Iodine 1 1 Permanent
marker 1 1 1 1 1 5 Moderate #2 Pencil 1 1 2 Wax Crayon 1 1 2 Shoe
Polish 1 1 1 3 Total 23
RESULTS
[0130] 1. The Polyester/Melamine coated sample showed no evidence
of coating cracking after thermoforming.
[0131] 2. The Polyester/Melamine sample showed greater Hoffman
Scratch resistance and greater burnish resistance compared to the
Melamine/Fluorinated Poly-oxetane Polyester sample.
[0132] 3. The Polyester/Melamine coated sample yielded fewer MEK
wipes than the Melamine/Fluoronated Poly-oxetane Polyester
sample.
[0133] Overall, the Polyester/Melamine coated sample showed good
solvent resistance and durability (scratch and mar). Stain
resistance was poorer than the Melamine/Fluorinated Poly-oxetane
Polyester coated sample.
[0134] While in accordance with the patent statutes the best mode
and preferred embodiment have been set forth, the scope of the
invention is not intended to be limited thereto, but only by the
scope of the attached claims.
* * * * *